Abstract: Two types of bifilar winding on the secondary of a high – power pulse transformer are disussed. Because of some voltage nonequilibrium between two windings and load asymmetrical disposition for the windings the pulse energy will intrude into the cathode heater. The factors which affect the pulse heating energy are the load disposition, the HV pulse equilibrium level between two windings, the pulse width and amplitude, the value of equilibrium capacitor, the equivalent heater resistance, and pulse transformer parameters etc. of which the main factor is the load disposition. The quantitative results show that load symmetrical disposition has a notable advantage and the pulse heating energy after a pulse is much greater than during the pulse.